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 <body class="h-entry">
  <div class="head">
   <p data-fill-with="logo"><a class="logo" href="https://www.w3.org/"> <img alt="W3C" height="48" src="https://www.w3.org/StyleSheets/TR/2016/logos/W3C" width="72"> </a> </p>
   <h1 class="p-name no-ref" id="title">CSS Generated Content for Paged Media Module</h1>
   <h2 class="no-num no-toc no-ref heading settled" id="subtitle"><span class="content">Editor’s Draft, <time class="dt-updated" datetime="1970-01-01">1 January 1970</time></span></h2>
   <details>
    <summary>Specification Metadata</summary>
    <div data-fill-with="spec-metadata">
     <dl>
      <dt>This version:
      <dd><a class="u-url" href="https://drafts.csswg.org/css-gcpm/">https://drafts.csswg.org/css-gcpm/</a>
      <dt>Latest published version:
      <dd><a href="https://www.w3.org/TR/css-gcpm-3/">https://www.w3.org/TR/css-gcpm-3/</a>
      <dt>Previous Versions:
      <dd><a href="https://www.w3.org/TR/2014/WD-css-gcpm-3-20140513/" rel="prev">https://www.w3.org/TR/2014/WD-css-gcpm-3-20140513/</a>
      <dd><a href="https://hg.csswg.org/drafts/raw-file/6a5c44d11c2b/css-gcpm/Overview.html" rel="prev">https://hg.csswg.org/drafts/raw-file/6a5c44d11c2b/css-gcpm/Overview.html</a>
      <dd><a href="https://www.w3.org/TR/2011/WD-css3-gcpm-20111129/" rel="prev">https://www.w3.org/TR/2011/WD-css3-gcpm-20111129/</a>
      <dt>Test Suite:
      <dd><a href="http://test.csswg.org/suites/css-gcpm-3_dev/nightly-unstable/">http://test.csswg.org/suites/css-gcpm-3_dev/nightly-unstable/</a>
      <dt class="editor">Editor:
      <dd class="editor p-author h-card vcard" data-editor-id="65283"><a class="p-name fn u-email email" href="mailto:dave.cramer@hbgusa.com">Dave Cramer</a> (<span class="p-org org">Hachette Livre</span>)
      <dt class="editor">Former Editor:
      <dd class="editor p-author h-card vcard"><span class="p-name fn">Håkon Wium Lie</span> (<span class="p-org org">Opera Software</span>)
      <dt>Suggest an Edit for this Spec:
      <dd><a href="https://github.com/w3c/csswg-drafts/blob/master/css-gcpm-3/Overview.bs">GitHub Editor</a>
      <dt>Issue Tracking:
      <dd><a href="https://github.com/w3c/csswg-drafts/labels/css-gcpm-3">GitHub Issues</a>
     </dl>
    </div>
   </details>
   <div data-fill-with="warning"></div>
   <p class="copyright" data-fill-with="copyright"><a href="https://www.w3.org/Consortium/Legal/ipr-notice#Copyright">Copyright</a> © 1970 <a href="https://www.w3.org/"><abbr title="World Wide Web Consortium">W3C</abbr></a><sup>®</sup> (<a href="https://www.csail.mit.edu/"><abbr title="Massachusetts Institute of Technology">MIT</abbr></a>, <a href="https://www.ercim.eu/"><abbr title="European Research Consortium for Informatics and Mathematics">ERCIM</abbr></a>, <a href="https://www.keio.ac.jp/">Keio</a>, <a href="https://ev.buaa.edu.cn/">Beihang</a>). W3C <a href="https://www.w3.org/Consortium/Legal/ipr-notice#Legal_Disclaimer">liability</a>, <a href="https://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</a> and <a href="https://www.w3.org/Consortium/Legal/2015/copyright-software-and-document">permissive document license</a> rules apply. </p>
   <hr title="Separator for header">
  </div>
  <div class="p-summary" data-fill-with="abstract">
   <h2 class="no-num no-toc no-ref heading settled" id="abstract"><span class="content">Abstract</span></h2>
   <p>Books and other paged media often use special techniques to display information. Content may be moved to or generated for special areas of the page, such as running heads or footnotes. Generated content within pages, such as tab leaders or cross-references, helps readers navigate within and between pages.</p>
    <a href="https://www.w3.org/TR/CSS/">CSS</a> is a language for describing the rendering of structured documents
(such as HTML and XML)
on screen, on paper, etc. 
  </div>
  <h2 class="no-num no-toc no-ref heading settled" id="status"><span class="content">Status of this document</span></h2>
  <div data-fill-with="status">
   <p> This is a public copy of the editors’ draft.
	It is provided for discussion only and may change at any moment.
	Its publication here does not imply endorsement of its contents by W3C.
	Don’t cite this document other than as work in progress. </p>
   <p> <a href="https://github.com/w3c/csswg-drafts/issues">GitHub Issues</a> are preferred for discussion of this specification.
	When filing an issue, please put the text “css-gcpm” in the title,
	preferably like this:
	“[css-gcpm] <i data-lt>…summary of comment…</i>”.
	All issues and comments are <a href="https://lists.w3.org/Archives/Public/public-css-archive/">archived</a>,
	and there is also a <a href="https://lists.w3.org/Archives/Public/www-style/">historical archive</a>. </p>
   <p> This document was produced by the <a href="https://www.w3.org/Style/CSS/">CSS Working Group</a>. </p>
   <p> This document was produced by a group operating under
	the <a href="https://www.w3.org/Consortium/Patent-Policy/">W3C Patent Policy</a>.
	W3C maintains a <a href="https://www.w3.org/2004/01/pp-impl/32061/status" rel="disclosure">public list of any patent disclosures</a> made in connection with the deliverables of the group;
	that page also includes instructions for disclosing a patent.
	An individual who has actual knowledge of a patent which the individual believes contains <a href="https://www.w3.org/Consortium/Patent-Policy/#def-essential">Essential Claim(s)</a> must disclose the information in accordance with <a href="https://www.w3.org/Consortium/Patent-Policy/#sec-Disclosure">section 6 of the W3C Patent Policy</a>. </p>
   <p> This document is governed by the <a href="https://www.w3.org/2019/Process-20190301/" id="w3c_process_revision">1 March 2019 W3C Process Document</a>. </p>
   <p></p>
  </div>
  <div data-fill-with="at-risk"></div>
  <nav data-fill-with="table-of-contents" id="toc">
   <h2 class="no-num no-toc no-ref" id="contents">Table of Contents</h2>
   <ol class="toc" role="directory">
    <li><a href="#introduction"><span class="secno"></span> <span class="content"> Introduction </span></a>
    <li>
     <a href="#running-headers-and-footers"><span class="secno">1</span> <span class="content"> Running headers and footers </span></a>
     <ol class="toc">
      <li>
       <a href="#named-strings"><span class="secno">1.1</span> <span class="content"> Named strings </span></a>
       <ol class="toc">
        <li>
         <a href="#setting-named-strings-the-string-set-pro"><span class="secno">1.1.1</span> <span class="content"> The string-set property </span></a>
         <ol class="toc">
          <li><a href="#content-function-header"><span class="secno">1.1.1.1</span> <span class="content">The <span class="css">content()</span> function</span></a>
         </ol>
        <li><a href="#using-named-strings"><span class="secno">1.1.2</span> <span class="content"> The <span class="css">string()</span> function </span></a>
       </ol>
      <li>
       <a href="#running-elements"><span class="secno">1.2</span> <span class="content"> Running elements </span></a>
       <ol class="toc">
        <li><a href="#running-syntax"><span class="secno">1.2.1</span> <span class="content"> The <span class="css">running()</span> value </span></a>
        <li><a href="#element-syntax"><span class="secno">1.2.2</span> <span class="content"> The <span class="css">element()</span> value </span></a>
       </ol>
     </ol>
    <li>
     <a href="#footnotes"><span class="secno">2</span> <span class="content"> Footnotes </span></a>
     <ol class="toc">
      <li><a href="#footnote-terms"><span class="secno">2.1</span> <span class="content">Terminology</span></a>
      <li><a href="#creating-footnotes"><span class="secno">2.2</span> <span class="content"> Creating footnotes </span></a>
      <li><a href="#footnote-types"><span class="secno">2.3</span> <span class="content"> Types of footnotes </span></a>
      <li>
       <a href="#footnote-area"><span class="secno">2.4</span> <span class="content"> The footnote area </span></a>
       <ol class="toc">
        <li><a href="#footnote-area-position"><span class="secno">2.4.1</span> <span class="content">Positioning of the footnote area</span></a>
        <li><a href="#footnote-area-size"><span class="secno">2.4.2</span> <span class="content">Size of the footnote area</span></a>
       </ol>
      <li>
       <a href="#footnote-counters"><span class="secno">2.5</span> <span class="content">The Footnote Counter</span></a>
       <ol class="toc">
        <li><a href="#footnote-counter-values"><span class="secno">2.5.1</span> <span class="content">Values of the footnote counter</span></a>
        <li><a href="#resetting-footnote-counter"><span class="secno">2.5.2</span> <span class="content">Resetting the footnote counter</span></a>
       </ol>
      <li><a href="#footnote-call"><span class="secno">2.6</span> <span class="content"> The <code>footnote-call</code> pseudo-element </span></a>
      <li><a href="#footnote-marker"><span class="secno">2.7</span> <span class="content"> The <code>footnote-marker</code> pseudo-element </span></a>
      <li><a href="#footnote-policy"><span class="secno">2.8</span> <span class="content"> Rendering footnotes and <code>footnote policy</code> </span></a>
      <li><a href="#future"><span class="secno">2.9</span> <span class="content"> Future directions </span></a>
     </ol>
    <li>
     <a href="#the-first-page-pseudo-element"><span class="secno">3</span> <span class="content"> Selecting Pages </span></a>
     <ol class="toc">
      <li><a href="#document-page-selectors"><span class="secno">3.1</span> <span class="content"> Page Selectors </span></a>
      <li><a href="#document-sequence-selectors"><span class="secno">3.2</span> <span class="content"> Page groups </span></a>
     </ol>
    <li><a href="#leaders"><span class="secno">4</span> <span class="content"> Leaders (moved) </span></a>
    <li><a href="#cross-references"><span class="secno">5</span> <span class="content"> Cross-references (moved) </span></a>
    <li><a href="#bookmarks"><span class="secno">6</span> <span class="content"> Bookmarks (moved) </span></a>
    <li>
     <a href="#former-wd-sections"><span class="secno"></span> <span class="content">Appendix A: Where Are They Now?</span></a>
     <ol class="toc">
      <li><a href="#page-marks-and-bleed-area"><span class="secno"></span> <span class="content">Page marks and bleed area</span></a>
      <li><a href="#cmyk-colors"><span class="secno"></span> <span class="content">CMYK colors</span></a>
      <li><a href="#styling-blank-pages"><span class="secno"></span> <span class="content">Styling blank pages</span></a>
      <li><a href="#paged-presentations"><span class="secno"></span> <span class="content">Paged presentations</span></a>
      <li><a href="#navigation-between-pages"><span class="secno"></span> <span class="content">Navigation between pages</span></a>
      <li><a href="#page-floats"><span class="secno"></span> <span class="content">Page floats</span></a>
      <li><a href="#selecting-columns-and-pages"><span class="secno"></span> <span class="content">Selecting columns and pages</span></a>
     </ol>
    <li><a href="#ua-stylesheet"><span class="secno"></span> <span class="content">Appendix B: Default UA Stylesheet</span></a>
    <li><a href="#changes"><span class="secno"></span> <span class="content">Appendix C: Changes</span></a>
    <li><a href="#acknowledgments"><span class="secno"></span> <span class="content"> Acknowledgments </span></a>
    <li>
     <a href="#conformance"><span class="secno"></span> <span class="content"> Conformance</span></a>
     <ol class="toc">
      <li><a href="#document-conventions"><span class="secno"></span> <span class="content"> Document conventions</span></a>
      <li><a href="#conform-classes"><span class="secno"></span> <span class="content"> Conformance classes</span></a>
      <li>
       <a href="#conform-responsible"><span class="secno"></span> <span class="content"> Requirements for Responsible Implementation of CSS</span></a>
       <ol class="toc">
        <li><a href="#conform-partial"><span class="secno"></span> <span class="content"> Partial Implementations</span></a>
        <li><a href="#conform-future-proofing"><span class="secno"></span> <span class="content"> Implementations of Unstable and Proprietary Features</span></a>
        <li><a href="#conform-testing"><span class="secno"></span> <span class="content"> Implementations of CR-level Features</span></a>
       </ol>
     </ol>
    <li>
     <a href="#index"><span class="secno"></span> <span class="content">Index</span></a>
     <ol class="toc">
      <li><a href="#index-defined-here"><span class="secno"></span> <span class="content">Terms defined by this specification</span></a>
      <li><a href="#index-defined-elsewhere"><span class="secno"></span> <span class="content">Terms defined by reference</span></a>
     </ol>
    <li>
     <a href="#references"><span class="secno"></span> <span class="content">References</span></a>
     <ol class="toc">
      <li><a href="#normative"><span class="secno"></span> <span class="content">Normative References</span></a>
      <li><a href="#informative"><span class="secno"></span> <span class="content">Informative References</span></a>
     </ol>
    <li><a href="#property-index"><span class="secno"></span> <span class="content">Property Index</span></a>
    <li><a href="#issues-index"><span class="secno"></span> <span class="content">Issues Index</span></a>
   </ol>
  </nav>
  <main>
   <h2 class="no-num heading settled" id="introduction"><span class="content"> Introduction </span></h2>
   <p>Paged media have many <a href="http://w3c.github.io/dpub-pagination/index.html">special requirements</a> for the display of document content, which have evolved over the long history of printed books. Running headers and footers function as aids to navigation. Notes may appear at the bottom of the page, as footnotes. The properties of pages themselves may change based on their content or position in the document. Leaders visually connect related content. Cross-references may require generated text. Some paged media formats such as PDF use bookmarks for navigation.</p>
   <p>This module defines new properties and values, so that authors may bring these techniques to paged media.</p>
   <h2 class="heading settled" data-level="1" id="running-headers-and-footers"><span class="secno">1. </span><span class="content"> Running headers and footers </span><a class="self-link" href="#running-headers-and-footers"></a></h2>
    <a data-link-type="biblio" href="#biblio-css3page">[CSS3PAGE]</a> describes the sixteen page margin boxes which can be used for running headers and footers, but does not describe a mechanism for inserting content in those boxes. This module provides two methods for for doing so. <dfn data-dfn-type="dfn" data-lt="named string" data-noexport id="named-string">Named strings<a class="self-link" href="#named-string"></a></dfn> copy text for reuse in margin boxes. <dfn data-dfn-type="dfn" data-noexport id="running-elements0">Running elements<a class="self-link" href="#running-elements0"></a></dfn> move elements (complete with style and structure) from the document to margin boxes. 
   <h3 class="heading settled" data-level="1.1" id="named-strings"><span class="secno">1.1. </span><span class="content"> Named strings </span><a class="self-link" href="#named-strings"></a></h3>
    The <a class="property" data-link-type="propdesc" href="#propdef-string-set" id="ref-for-propdef-string-set">string-set</a> property copies the text content of an element into a <span class="css">named string</span>, which functions as a variable. The text content of this named string can be retrieved using the <a class="css" data-link-type="maybe" href="#funcdef-string" id="ref-for-funcdef-string">string()</a> function. Since these variables may change on a given page, an optional second value for the <span class="css" id="ref-for-funcdef-string①">string()</span> function allows authors to choose which value on a page is used. 
   <h4 class="heading settled" data-level="1.1.1" id="setting-named-strings-the-string-set-pro"><span class="secno">1.1.1. </span><span class="content"> The string-set property </span><a class="self-link" href="#setting-named-strings-the-string-set-pro"></a></h4>
   <table class="def propdef" data-link-for-hint="<dfn id=&quot;string-set&quot;>string-set</dfn>">
    <tbody>
     <tr>
      <th>Name:
      <td><dfn class="dfn-paneled css" data-dfn-type="property" data-export id="propdef-string-set">string-set</dfn>
     <tr class="value">
      <th><a href="https://drafts.csswg.org/css-values/#value-defs">Value:</a>
      <td class="prod">[[ <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#identifier-value" id="ref-for-identifier-value">&lt;custom-ident></a> <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-content-3/#typedef-content-content-list" id="ref-for-typedef-content-content-list" title="Expands to: <string> | close-quote | <image> | leader() | no-close-quote | no-open-quote | open-quote | contents">&lt;content-list></a>] [<a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-comma" id="ref-for-comb-comma">,</a> <span class="production" id="ref-for-identifier-value①">&lt;custom-ident></span> <span class="production" id="ref-for-typedef-content-content-list①" title="Expands to: <string> | close-quote | <image> | leader() | no-close-quote | no-open-quote | open-quote | contents">&lt;content-list></span>]<a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#mult-zero-plus" id="ref-for-mult-zero-plus">*</a> ] <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one">|</a> none
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#initial-values">Initial:</a>
      <td>none
     <tr>
      <th>Applies to:
      <td>all elements, but not pseudo-elements
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#inherited-property">Inherited:</a>
      <td>no
     <tr>
      <th><a href="https://drafts.csswg.org/css-values/#percentages">Percentages:</a>
      <td>N/A
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#computed">Computed value:</a>
      <td>specified value
     <tr>
      <th>Canonical order:
      <td>per grammar
     <tr>
      <th><a href="https://drafts.csswg.org/web-animations/#animation-type">Animation type:</a>
      <td>discrete
   </table>
   <p class="all-media">User Agents are expected to support this property on all media, including non-visual ones.</p>
   <p>The <a class="property" data-link-type="propdesc" href="#propdef-string-set" id="ref-for-propdef-string-set①">string-set</a> property contains one or more pairs, each consisting of an custom identifier (the name of the named string) followed by a <span class="css">content-list</span> describing how to construct the value of the named string.</p>
   <p><span class="css">content-list</span> expands to one or more of the following values, in any order.</p>
<pre class="prod"><dfn data-dfn-type="dfn" data-noexport id="content-list">content-list<a class="self-link" href="#content-list"></a></dfn> = [ &lt;string> <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one①">|</a> &lt;counter()> <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one②">|</a> &lt;counters()> <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one③">|</a> &lt;content()> <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one④">|</a> attr(&lt;identifier>) ]<a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#mult-one-plus" id="ref-for-mult-one-plus">+</a>
</pre>
   <dl>
    <dt> &lt;string> 
    <dd> A <a href="https://www.w3.org/TR/CSS21/syndata.html#strings">string</a>, as defined in <a data-link-type="biblio" href="#biblio-css21">[CSS21]</a> 
    <dt> &lt;counter()> 
    <dd> A <a href="https://www.w3.org/TR/CSS21/syndata.html#counter">counter()</a> function, as described in <a data-link-type="biblio" href="#biblio-css21">[CSS21]</a>.
    <dt> &lt;counters()> 
    <dd> A <a href="https://www.w3.org/TR/CSS21/syndata.html#counter">counters()</a> function, as described in <a data-link-type="biblio" href="#biblio-css21">[CSS21]</a>.
    <dt>content()
    <dd>The <a class="css" data-link-type="maybe" href="#funcdef-content" id="ref-for-funcdef-content">content()</a> function, described below.
    <dt>attr(&lt;identifier>)
    <dd>Returns the string value of the attribute &lt;identifier>, as defined in <a data-link-type="biblio" href="#biblio-css3val">[CSS3VAL]</a>
   </dl>
   <h5 class="heading settled" data-level="1.1.1.1" id="content-function-header"><span class="secno">1.1.1.1. </span><span class="content">The <a class="css" data-link-type="maybe" href="#funcdef-content" id="ref-for-funcdef-content①">content()</a> function</span><a class="self-link" href="#content-function-header"></a></h5>
<pre class="prod"><dfn class="dfn-paneled" data-dfn-type="function" data-export id="funcdef-content">content()</dfn> = content([text <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one⑤">|</a> before <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one⑥">|</a> after <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one⑦">|</a> first-letter ])
</pre>
   <p class="issue" id="issue-edcf4ca2"><a class="self-link" href="#issue-edcf4ca2"></a>How do we define the default value for this function?</p>
   <dl>
    <dt>text
    <dd>The string value of the element, determined as if <code>white-space: normal</code> had been set. This is the default value
    <dt>before
    <dd>The string value of the <code>::before</code> pseudo-element, determined as if <code>white-space: normal</code> had been set. 
    <dt>after
    <dd>The string value of the <code>::after</code> pseudo-element, determined as if <code>white-space: normal</code> had been set. 
    <dt>first-letter
    <dd>The first letter of the element, as defined for the <code><a href="https://www.w3.org/TR/css3-selectors/#first-letter">::first-letter</a></code> pseudo-element 
   </dl>
   <p>The content values of named strings are assigned at the point when the content box of the element is first created (or would have been created if the element’s display value is none). The <dfn data-dfn-type="dfn" data-noexport id="entry-value">entry value<a class="self-link" href="#entry-value"></a></dfn> for a page is the assignment in effect at the end of the previous page. The <dfn data-dfn-type="dfn" data-noexport id="exit-value">exit value<a class="self-link" href="#exit-value"></a></dfn> for a page is the assignment in effect at the end of the current page.</p>
   <p>Whenever the value of the element changes, the value of the named string(s) is updated. User agents must be able to recall many values of the named string, as the <a class="css" data-link-type="maybe" href="#funcdef-string" id="ref-for-funcdef-string②">string()</a> function can return past, current, or future values of the assignment.</p>
   <div class="example" id="example-e698ead2">
    <a class="self-link" href="#example-e698ead2"></a> 
    <p>HTML:</p>
<pre>&lt;h1>Loomings&lt;/h1>
</pre>
    <p>CSS:</p>
<pre>h1::before { content: 'Chapter ' counter(chapter); }
h1 { string-set: header content(before) ':' content(text); }
h1::after { content: '.'; }
</pre>
    <p>The value of the named string “header” will be “Chapter 1: Loomings”.</p>
   </div>
   <div class="example" id="example-ba54cbec">
    <a class="self-link" href="#example-ba54cbec"></a> HTML: 
<pre>&lt;section title="Loomings">
</pre>
    <p>CSS:</p>
<pre>section { string-set: header attr(title) }
</pre>
    <p>The value of the “header” string will be “Loomings”.</p>
   </div>
   <h4 class="heading settled" data-level="1.1.2" id="using-named-strings"><span class="secno">1.1.2. </span><span class="content"> The <a class="css" data-link-type="maybe" href="#funcdef-string" id="ref-for-funcdef-string③">string()</a> function </span><a class="self-link" href="#using-named-strings"></a></h4>
    The <span class="css" id="ref-for-funcdef-string④">string()</span> function is used to copy the value of a named string to the document, via the <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-content-3/#propdef-content" id="ref-for-propdef-content">content</a> property. This function requires one argument, the name of the named string. Since the value of a named string may change several times on a page (as new instances of the element defining the string appear) an optional second argument indicates which value of the named string should be used. 
<pre class="prod"><dfn class="dfn-paneled" data-dfn-type="function" data-export id="funcdef-string">string()</dfn> = string( <a class="production" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#identifier-value" id="ref-for-identifier-value②">&lt;custom-ident></a> [ <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-comma" id="ref-for-comb-comma①">,</a> [ first <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one⑧">|</a> start <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one⑨">|</a> last <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one①⓪">|</a> first-except] ]<a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#mult-opt" id="ref-for-mult-opt">?</a> )
</pre>
   <p>The second argument of the <a class="css" data-link-type="maybe" href="#funcdef-string" id="ref-for-funcdef-string⑤">string()</a> function is one of the following keywords:</p>
   <dl>
    <dt id="string-first"><a class="self-link" href="#string-first"></a>first
    <dd>The value of the first assignment on the page is used. If there is no assignment on the page, the <span class="css">entry value</span> is used. <code>first</code> is the default value.
    <dt id="string-start"><a class="self-link" href="#string-start"></a>start
    <dd>If the element is the first element on the page, the value of the first assignment is used. Otherwise the <span class="css">entry value</span> is used. The <span class="css">entry value</span> may be empty if the element hasn’t yet appeared. 
    <dt id="string-last"><a class="self-link" href="#string-last"></a>last
    <dd>The <span class="css">exit value</span> of the named string is used.
    <dt id="string-first-except"><a class="self-link" href="#string-first-except"></a>first-except
    <dd>This is identical to <code>first</code>, except that the empty string is used on the page where the value is assigned.
   </dl>
   <div class="example" id="example-23e3824c">
    <a class="self-link" href="#example-23e3824c"></a> CSS: 
<pre>@page {
   size: 15cm 10cm;
   margin: 1.5cm;

   @top-left {
   content: "first: " string(heading, first);
   }
   @top-center {
   content: "start: " string(heading, start);
   }
    @top-right {
    content: "last: " string(heading, last);
   }
  }

h2 { string-set: heading content() }
</pre>
    <p>The following figures show the first, start, and last assignments of the “heading” string on various pages.</p>
    <figure>
      <img alt src="images/using-strings-1.jpg" width="480"> 
     <figcaption>The <a href="#string-start">start</a> value is empty, as the string had not yet been set at the start of the page.</figcaption>
    </figure>
    <figure>
      <img alt src="images/using-strings-2.jpg" width="480"> 
     <figcaption>Since the page starts with an h2, the <a href="#string-start">start</a> value is the value of that head.</figcaption>
    </figure>
    <figure>
      <img alt src="images/using-strings-3.jpg" width="480"> 
     <figcaption>Since there’s not an h2 at the top of this page, the <a href="#string-start">start</a> value is the <span class="css">exit value</span> of the previous page.</figcaption>
    </figure>
   </div>
   <h3 class="heading settled" data-level="1.2" id="running-elements"><span class="secno">1.2. </span><span class="content"> Running elements </span><a class="self-link" href="#running-elements"></a></h3>
    Many headers and footers cannot be represented only by unformatted text. A book title serving as a running head may contain an italic word, for example. A mechanism is needed to move or copy elements into margin boxes. To do this, we add the <a class="css" data-link-type="maybe" href="#funcdef-running" id="ref-for-funcdef-running">running()</a> value to the position property, and the <a class="css" data-link-type="maybe" href="#funcdef-element" id="ref-for-funcdef-element">element()</a> value to the content property. 
   <div class="example" id="example-6cddf8e9">
    <a class="self-link" href="#example-6cddf8e9"></a> 
<pre>@page {
  @top { content: element(header); }
}

h1 { position: running(header); }
</pre>
    <p>In this example, the <code>h1</code> element is placed in the <code>@top</code> margin box, complete with formatting and any descendant elements. It does not display in the normal document flow.</p>
   </div>
   <h4 class="heading settled" data-level="1.2.1" id="running-syntax"><span class="secno">1.2.1. </span><span class="content"> The <a class="css" data-link-type="maybe" href="#funcdef-running" id="ref-for-funcdef-running①">running()</a> value </span><a class="self-link" href="#running-syntax"></a></h4>
   <p><code>position: running(custom-ident)</code> removes the element (and associated ::before and ::after pseudo-elements) from the normal flow, and makes it available to place in a page margin box using <a class="css" data-link-type="maybe" href="#funcdef-element" id="ref-for-funcdef-element①">element()</a>. The element inherits from its original position in the document, but does not display there.</p>
   <table class="def propdef partial" data-link-for-hint="position">
    <tbody>
     <tr>
      <th>Name:
      <td><a class="css" data-link-type="property" href="https://drafts.csswg.org/css-position-3/#propdef-position" id="ref-for-propdef-position">position</a>
     <tr class="value">
      <th><a href="https://drafts.csswg.org/css-values/#value-defs">New values:</a>
      <td class="prod">running()
   </table>
<pre class="prod"><dfn class="dfn-paneled" data-dfn-type="function" data-export id="funcdef-running">running()</dfn> = string( <a class="production" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#identifier-value" id="ref-for-identifier-value③">&lt;custom-ident></a> )
</pre>
   <div class="example" id="example-ffae16e8">
    <a class="self-link" href="#example-ffae16e8"></a> 
    <p>HTML:</p>
<pre>&lt;p class="rh">&lt;i>Miranda v. Arizona&lt;/i> in Context&lt;/p>
&lt;h2>&lt;i>Miranda v. Arizona&lt;/i> in Context&lt;/h2>
</pre>
    <p>CSS:</p>
<pre>@top-center {
  content: element(heading);
  }

p.rh {
  position: running(heading);
  }

p.rh::before {
  content: counter(page) ' / ';
  }
</pre>
    <figure>
     <p><img alt="running header using running elements" src="images/running-element-gcpm_Page_1.jpg" width="480"></p>
     <figcaption>Running element in page margin box</figcaption>
    </figure>
   </div>
   <p class="note" role="note">The element <span class="css">value()</span> can only be used in page margin boxes. And it cannot be combined with other possible values for the content property.</p>
   <div class="issue" id="issue-929df450">
    <a class="self-link" href="#issue-929df450"></a> 
    <p>This idea would be much more useful if we could also copy (rather than just move) elements. That would avoid the duplication of HTML in the example above. </p>
    <p>Bert Bos has proposed an alternative syntax, which allows both moving and copying elements into running heads. In the example below, h2 elements appear in their normal place in the document, but are also copied into running heads.</p>
    <div class="example" id="example-ffc3e328">
     <a class="self-link" href="#example-ffc3e328"></a> 
<pre>h2 {
display: block;
running: chapter;
font-size: 18pt;
font-weight: bold;
}

h2:running {
display: inline;
font-size: 11pt;
font-weight: normal;
font-variant: small-caps;
letter-spacing: 1pt;
}

@page {
  @top-center {
    content: element(chapter);
    }
  }
</pre>
    </div>
    <table class="def propdef" data-link-for-hint="<dfn id=&quot;running-property&quot;>running</dfn>">
     <tbody>
      <tr>
       <th>Name:
       <td><dfn class="css" data-dfn-type="property" data-export id="propdef-running">running<a class="self-link" href="#propdef-running"></a></dfn>
      <tr class="value">
       <th><a href="https://drafts.csswg.org/css-values/#value-defs">Value:</a>
       <td class="prod"><a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#identifier-value" id="ref-for-identifier-value④">&lt;custom-ident></a>
      <tr>
       <th><a href="https://drafts.csswg.org/css-cascade/#initial-values">Initial:</a>
       <td>none
      <tr>
       <th>Applies to:
       <td>elements
      <tr>
       <th><a href="https://drafts.csswg.org/css-cascade/#inherited-property">Inherited:</a>
       <td>no
      <tr>
       <th><a href="https://drafts.csswg.org/css-values/#percentages">Percentages:</a>
       <td>N/A
      <tr>
       <th><a href="https://drafts.csswg.org/css-cascade/#computed">Computed value:</a>
       <td>specified value
      <tr>
       <th>Canonical order:
       <td>per grammar
      <tr>
       <th><a href="https://drafts.csswg.org/web-animations/#animation-type">Animation type:</a>
       <td>discrete
    </table>
    <p class="all-media">User Agents are expected to support this property on all media, including non-visual ones.</p>
   </div>
   <h4 class="heading settled" data-level="1.2.2" id="element-syntax"><span class="secno">1.2.2. </span><span class="content"> The <a class="css" data-link-type="maybe" href="#funcdef-element" id="ref-for-funcdef-element②">element()</a> value </span><a class="self-link" href="#element-syntax"></a></h4>
   <p>The <a class="css" data-link-type="maybe" href="#funcdef-element" id="ref-for-funcdef-element③">element()</a> value of the content property places an element (which has been removed from the normal flow via <a class="css" data-link-type="maybe" href="#funcdef-running" id="ref-for-funcdef-running②">running()</a>) in a page margin box. Whenever the value of the element changes, the value of <span class="css" id="ref-for-funcdef-element④">element()</span> is updated.</p>
   <p>Just as with <a class="css" data-link-type="maybe" href="#funcdef-string" id="ref-for-funcdef-string⑥">string()</a>, <a class="css" data-link-type="maybe" href="#funcdef-element" id="ref-for-funcdef-element⑤">element()</a> takes an optional keyword to describe which value should be used in the case of multiple assignments on a page. User agents must be able to recall many values, as <span class="css" id="ref-for-funcdef-element⑥">element()</span> can return past, current, or future values of the assignment.</p>
   <table class="def propdef partial" data-link-for-hint="content">
    <tbody>
     <tr>
      <th>Name:
      <td><a class="css" data-link-type="property" href="https://drafts.csswg.org/css-content-3/#propdef-content" id="ref-for-propdef-content①">content</a>
     <tr class="value">
      <th><a href="https://drafts.csswg.org/css-values/#value-defs">New values:</a>
      <td class="prod">element()
   </table>
<pre class="prod"><dfn class="dfn-paneled" data-dfn-type="function" data-export id="funcdef-element">element()</dfn> = string( <a class="production" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#identifier-value" id="ref-for-identifier-value⑤">&lt;custom-ident></a> [ <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-comma" id="ref-for-comb-comma②">,</a> [ first <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one①①">|</a> start <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one①②">|</a> last <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one①③">|</a> first-except] ]<a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#mult-opt" id="ref-for-mult-opt①">?</a> )
</pre>
   <h2 class="heading settled" data-level="2" id="footnotes"><span class="secno">2. </span><span class="content"> Footnotes </span><a class="self-link" href="#footnotes"></a></h2>
    Ancillary content may be moved to the bottom or side of a page. A footnote is created when such content moves to the bottom of the page, leaving a reference indicator. 
   <h3 class="heading settled" data-level="2.1" id="footnote-terms"><span class="secno">2.1. </span><span class="content">Terminology</span><a class="self-link" href="#footnote-terms"></a></h3>
   <p>Footnotes are complex objects (see the <a href="https://www.w3.org/TR/2014/WD-dpub-latinreq-20140313/#footnotes">footnote section</a> at <a data-link-type="biblio" href="#biblio-dpub-latinreq">[dpub-latinreq]</a>), so it will be helpful to define some terms before proceeding.</p>
   <figure>
    <p><img alt="page with footnotes" src="images/footnote-diagram.001.jpg" width="480"></p>
    <figcaption>Footnote terminology</figcaption>
   </figure>
   <dl>
    <dt>footnote element
    <dd>The element containing the content of the footnote, which will be removed from the flow and displayed as a footnote.
    <dt>footnote marker (also known as footnote number)
    <dd>A number or symbol adjacent to the footnote body, identifying the particular footnote. The footnote marker should use the same number or symbol as the corresponding footnote call, although the marker may contain additional punctuation.
    <dt>footnote body
    <dd>The footnote marker is placed before the footnote element, and together they represent the footnote body, which will be placed in the footnote area.
    <dt>footnote call (also known as footnote reference)
    <dd>A number or symbol, found in the main text, which points to the footnote body.
    <dt>footnote area
    <dd>The page area used to display footnotes.
    <dt>footnote rule (also known as footnote separator)
    <dd>A horizontal rule is often used to separate the footnote area from the rest of the page. The separator (and the entire footnote area) cannot be rendered on a page with no footnotes.
   </dl>
   <h3 class="heading settled" data-level="2.2" id="creating-footnotes"><span class="secno">2.2. </span><span class="content"> Creating footnotes </span><a class="self-link" href="#creating-footnotes"></a></h3>
    An element becomes a footnote by applying <code>float: footnote</code> to that element. This triggers the following actions: 
   <ol>
    <li> The footnote element is removed from the flow, and a <code>::footnote-call</code> pseudo-element is inserted in its place, which serves as a reference to the footnote.
    <li> A <code>::footnote-marker</code> pseudo-element, identifying the footnote, is placed at the beginning of the footnote element. Together this is the footnote body.
    <li>The <span class="css">footnote counter</span> is incremented.
    <li>The footnote body is placed in the footnote area at the bottom of the page. Footnote elements from a given page are placed in the footnote area of that page in document order.
   </ol>
   <div class="example" id="example-efe978c0">
    <a class="self-link" href="#example-efe978c0"></a> HTML: 
<pre style="word-wrap: break-word; white-space: pre-wrap;">&lt;p>Though the body was erect, the head was thrown back so that the closed eyes were pointed towards the needle of the tell-tale that swung from a beam in the ceiling.&lt;span class="footnote">The cabin-compass is called the tell-tale, because without going to the compass at the helm, the Captain, while below, can inform himself of the course of the ship.&lt;/span>&lt;/p>
</pre>
    <p>CSS:</p>
<pre>@page {
  @footnote {
    float: bottom;
  }
}

span.footnote { float: footnote; }
</pre>
   </div>
   <p class="issue" id="issue-4af1f674"><a class="self-link" href="#issue-4af1f674"></a>Why is float:bottom used with the footnote area? Floating footnotes to the footnote area, and then floating the footnote area itself, seems overly complex, given that implementations don’t allow the footnote area to float anywhere else. Note that some implementations do allow the footnote area to be absolutely positioned.</p>
   <h3 class="heading settled" data-level="2.3" id="footnote-types"><span class="secno">2.3. </span><span class="content"> Types of footnotes </span><a class="self-link" href="#footnote-types"></a></h3>
    The following new value of the <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css2/visuren.html#propdef-float" id="ref-for-propdef-float">float</a> property creates a footnote element: 
   <table class="def propdef partial" data-link-for-hint="float">
    <tbody>
     <tr>
      <th>Name:
      <td><a class="css" data-link-type="property" href="https://drafts.csswg.org/css2/visuren.html#propdef-float" id="ref-for-propdef-float①">float</a>
     <tr class="value">
      <th><a href="https://drafts.csswg.org/css-values/#value-defs">New values:</a>
      <td class="prod">footnote
   </table>
   <dl>
    <dt><dfn class="css" data-dfn-for="float" data-dfn-type="value" data-export id="valdef-float-footnote">footnote<a class="self-link" href="#valdef-float-footnote"></a></dfn>
    <dd>each footnote element is placed in the footnote area of the page
   </dl>
   <p>The <a class="property" data-link-type="propdesc" href="#propdef-footnote-display" id="ref-for-propdef-footnote-display">footnote-display</a> property determines whether a footnote is displayed as a block element or inline element.</p>
   <table class="def propdef" data-link-for-hint="<dfn id=&quot;propdef-footnote-display&quot;>footnote-display</dfn>">
    <tbody>
     <tr>
      <th>Name:
      <td><dfn class="dfn-paneled css" data-dfn-type="property" data-export id="propdef-footnote-display">footnote-display</dfn>
     <tr class="value">
      <th><a href="https://drafts.csswg.org/css-values/#value-defs">Value:</a>
      <td class="prod">block <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one①④">|</a> inline <span id="ref-for-comb-one①⑤">|</span> compact
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#initial-values">Initial:</a>
      <td>block
     <tr>
      <th>Applies to:
      <td>elements
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#inherited-property">Inherited:</a>
      <td>no
     <tr>
      <th><a href="https://drafts.csswg.org/css-values/#percentages">Percentages:</a>
      <td>N/A
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#computed">Computed value:</a>
      <td>specified value
     <tr>
      <th>Canonical order:
      <td>per grammar
     <tr>
      <th><a href="https://drafts.csswg.org/web-animations/#animation-type">Animation type:</a>
      <td>discrete
   </table>
   <dl>
    <dt><dfn class="css" data-dfn-for="propdef-footnote-display" data-dfn-type="value" data-export id="footnote-display-block">block<a class="self-link" href="#footnote-display-block"></a></dfn>
    <dd>The footnote element is placed in the footnote area as a block element
    <dt><dfn class="css" data-dfn-for="propdef-footnote-display" data-dfn-type="value" data-export id="footnote-display-inline">inline<a class="self-link" href="#footnote-display-inline"></a></dfn>
    <dd>The footnote element is placed in the footnote area as an inline element
    <dt><dfn class="css" data-dfn-for="propdef-footnote-display" data-dfn-type="value" data-export id="footnote-display-compact">compact<a class="self-link" href="#footnote-display-compact"></a></dfn>
    <dd>The user agent determines whether a given footnote element is placed as a block element or an inline element. If two or more footnotes could fit on the same line in the footnote area, they should be placed inline.
   </dl>
   <h3 class="heading settled" data-level="2.4" id="footnote-area"><span class="secno">2.4. </span><span class="content"> The footnote area </span><a class="self-link" href="#footnote-area"></a></h3>
    A <a href="https://drafts.csswg.org/css-page/#page-area">page area</a> that can be used to display footnotes is described in the <a href="https://drafts.csswg.org/css-page/#page-context">page context</a> using an <code>@footnote</code> rule. This rule defines a box that, if used, will contain all the footnote elements that appear on that page. 
   <p class="issue" id="issue-829ce977"><a class="self-link" href="#issue-829ce977"></a>How would one describe this in the grammar of CSS3-Page?</p>
   <h4 class="heading settled" data-level="2.4.1" id="footnote-area-position"><span class="secno">2.4.1. </span><span class="content">Positioning of the footnote area</span><a class="self-link" href="#footnote-area-position"></a></h4>
    The bottom margin edge of the footnote area is positioned so that it touches the bottom of the page area. The footnote area can only contain footnotes. 
   <p class="issue" id="issue-069a39a3"><a class="self-link" href="#issue-069a39a3"></a>How do footnotes work in multi-column text? Prince uses <code>float: prince-column-footnote</code> to create a footnote at the bottom of a column rather than the bottom of a page.</p>
   <p class="issue" id="issue-34f910d8"><a class="self-link" href="#issue-34f910d8"></a>Implementations that support footnotes generally support page floats like <code>float: bottom</code>. Page floats should end up above the footnote area. How might this be specified?</p>
   <h4 class="heading settled" data-level="2.4.2" id="footnote-area-size"><span class="secno">2.4.2. </span><span class="content">Size of the footnote area</span><a class="self-link" href="#footnote-area-size"></a></h4>
   <p>The <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css2/visudet.html#propdef-max-height" id="ref-for-propdef-max-height">max-height</a> property on the footnote area limits the size of this area, unless the page contains only footnotes (as may happen on the last page of a document).</p>
   <p>Since it is undesirable for a page to consist only of footnotes, user agents <em class="RFC2119">may</em> set a default max-height value on the footnote area.</p>
   <h3 class="heading settled" data-level="2.5" id="footnote-counters"><span class="secno">2.5. </span><span class="content">The Footnote Counter</span><a class="self-link" href="#footnote-counters"></a></h3>
   <p>The <dfn data-dfn-type="dfn" data-noexport id="footnote-counter">footnote counter<a class="self-link" href="#footnote-counter"></a></dfn> is a predefined <a href="https://drafts.csswg.org/css-lists/#counter">counter</a> associated with the footnote element. Its value is the number or symbol used to identify the footnote. This value is used in both the footnote call and the footnote marker. It should be incremented for each footnote.</p>
   <h4 class="heading settled" data-level="2.5.1" id="footnote-counter-values"><span class="secno">2.5.1. </span><span class="content">Values of the footnote counter</span><a class="self-link" href="#footnote-counter-values"></a></h4>
   <p>The footnote counter, like other counters, may use any <a href="https://drafts.csswg.org/css-counter-styles-3/#counter-style">counter style</a>. Footnotes often use a sequence of symbols.</p>
   <div class="example" id="example-e4cc5734">
    <a class="self-link" href="#example-e4cc5734"></a> 
<pre>::footnote-call { content: counter(footnote, symbols('*', '†', '‡', '§')); }

::footnote-marker { content: counter(footnote, symbols('*', '†', '‡', '§')) '. '; }
</pre>
   </div>
   <h4 class="heading settled" data-level="2.5.2" id="resetting-footnote-counter"><span class="secno">2.5.2. </span><span class="content">Resetting the footnote counter</span><a class="self-link" href="#resetting-footnote-counter"></a></h4>
   <p>The footnote counter may be reset on each page.</p>
   <div class="example" id="example-50e9e077">
    <a class="self-link" href="#example-50e9e077"></a> 
<pre>@page {
  counter-reset: footnote;
  @footnote { … }
}
</pre>
   </div>
   <p>Note that the value of the footnote counter should depend on the position of the footnote element in the document tree, not where it is eventually placed. A footnote element may sometimes be placed on the page after the footnote call, but the same counter value must be used for both.</p>
   <h3 class="heading settled" data-level="2.6" id="footnote-call"><span class="secno">2.6. </span><span class="content"> The <code>footnote-call</code> pseudo-element </span><a class="self-link" href="#footnote-call"></a></h3>
    A <code>::footnote-call</code> pseudo-element is inserted in place of the footnote element when the latter is removed from the flow. By default, the content of this pseudo-element is the value of the footnote counter, styled as a superscripted number. 
   <div class="example" id="example-eda00cbe">
    <a class="self-link" href="#example-eda00cbe"></a> 
<pre>::footnote-call {
content: counter(footnote);
vertical-align: baseline;
font-size: 100%;
line-height: inherit;
font-variant-position: super;
}
</pre>
   </div>
   <h3 class="heading settled" data-level="2.7" id="footnote-marker"><span class="secno">2.7. </span><span class="content"> The <code>footnote-marker</code> pseudo-element </span><a class="self-link" href="#footnote-marker"></a></h3>
    The <code>::footnote-marker</code> pseudo-element represents the footnote element’s marker, the number or symbol that identifies each footnote. This pseudo-element behaves like a <code>::marker</code> pseudo-element, as defined in <a data-link-type="biblio" href="#biblio-css3list">[CSS3LIST]</a>. It is placed at the beginning of the superior parent’s content, and is inline by default. The <code>::footnote-marker</code> can be styled just as other <code>::marker</code> elements can be. The default style should include <code>list-style-position: inside</code>. 
   <div class="example" id="example-64cfffb1">
    <a class="self-link" href="#example-64cfffb1"></a> 
<pre>::footnote-marker {
content: counter(footnote);
}

::footnote-marker::after {
content: '. ';
}
</pre>
   </div>
   <h3 class="heading settled" data-level="2.8" id="footnote-policy"><span class="secno">2.8. </span><span class="content"> Rendering footnotes and <code>footnote policy</code> </span><a class="self-link" href="#footnote-policy"></a></h3>
   <p>Rendering footnotes can be complex. If a footnote falls near the bottom of the page, there may not be enough room on the page for the footnote body. The <a class="property" data-link-type="propdesc" href="#propdef-footnote-policy" id="ref-for-propdef-footnote-policy">footnote-policy</a> property allows authors some influence over the rendering of difficult pages.</p>
   <table class="def propdef" data-link-for-hint="<dfn id=&quot;footnote-policy&quot;>footnote-policy</dfn>">
    <tbody>
     <tr>
      <th>Name:
      <td><dfn class="dfn-paneled css" data-dfn-type="property" data-export id="propdef-footnote-policy">footnote-policy</dfn>
     <tr class="value">
      <th><a href="https://drafts.csswg.org/css-values/#value-defs">Value:</a>
      <td class="prod">auto <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one①⑥">|</a> line <span id="ref-for-comb-one①⑦">|</span> block
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#initial-values">Initial:</a>
      <td>auto
     <tr>
      <th>Applies to:
      <td>elements
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#inherited-property">Inherited:</a>
      <td>no
     <tr>
      <th><a href="https://drafts.csswg.org/css-values/#percentages">Percentages:</a>
      <td>N/A
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#computed">Computed value:</a>
      <td>specified value
     <tr>
      <th>Canonical order:
      <td>per grammar
     <tr>
      <th><a href="https://drafts.csswg.org/web-animations/#animation-type">Animation type:</a>
      <td>discrete
   </table>
   <dl>
    <dt><dfn class="css" data-dfn-for="footnote-policy" data-dfn-type="value" data-export id="valdef-footnote-policy-auto">auto<a class="self-link" href="#valdef-footnote-policy-auto"></a></dfn>
    <dd>The user agent chooses how to render footnotes, and may place the footnote body on a later page than the footnote reference. A footnote body must never be placed on a page before the footnote reference.
    <dt><dfn class="dfn-paneled css" data-dfn-for="footnote-policy" data-dfn-type="value" data-export id="footnote-policy-line">line</dfn>
    <dd>If a given footnote body cannot be placed on the current page due to lack of space, the user agent introduces a forced page break at the start of the line containing the footnote reference, so that both the reference and the footnote body fall on the next page. Note that the user agent must honor <a href="https://drafts.csswg.org/css-break/#widows-orphans">widow and orphan</a> settings when doing this, and so may need to insert the page break on an earlier line.
    <dt><dfn class="css" data-dfn-for="footnote-policy" data-dfn-type="value" data-export id="valdef-footnote-policy-block">block<a class="self-link" href="#valdef-footnote-policy-block"></a></dfn>
    <dd>As with <a href="#footnote-policy-line" id="ref-for-footnote-policy-line">line</a>, except a forced page break is introduced before the paragraph that contains the footnote.
   </dl>
   <p class="issue" id="issue-da883bb8"><a class="self-link" href="#issue-da883bb8"></a>We need an algorithm for laying out footnotes</p>
   <h3 class="heading settled" data-level="2.9" id="future"><span class="secno">2.9. </span><span class="content"> Future directions </span><a class="self-link" href="#future"></a></h3>
    The next level will include sidenotes, column footnotes, and multiple footnote areas. 
   <h2 class="heading settled" data-level="3" id="the-first-page-pseudo-element"><span class="secno">3. </span><span class="content"> Selecting Pages </span><a class="self-link" href="#the-first-page-pseudo-element"></a></h2>
   <p>A paginated document consists of a sequence of pages. <a data-link-type="biblio" href="#biblio-css3page">[CSS3PAGE]</a> defines <dfn data-dfn-type="dfn" data-noexport id="page-selectors">page selectors<a class="self-link" href="#page-selectors"></a></dfn>, which allow the selection of the first page of the document, left and right pages, and blank pages. Here we extend the idea of page selectors to enable the selection of arbitrary document pages.</p>
   <h3 class="heading settled" data-level="3.1" id="document-page-selectors"><span class="secno">3.1. </span><span class="content"> Page Selectors </span><a class="self-link" href="#document-page-selectors"></a></h3>
    The <a class="css" data-link-type="maybe" href="#funcdef-nth" id="ref-for-funcdef-nth">nth()</a> page pseudo-class allows the selection of arbitrary document pages. This pseudo-class takes an argument of the form <a href="https://drafts.csswg.org/css-syntax/#anb">An + B</a> as defined in <a data-link-type="biblio" href="#biblio-css3syn">[CSS3SYN]</a>. When applied to the default @page rule, <span class="css" id="ref-for-funcdef-nth①">nth()</span> selects the document page whose index matches the argument. 
<pre class="prod"><dfn class="dfn-paneled" data-dfn-type="function" data-export id="funcdef-nth">nth()</dfn> = ( An<a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#mult-one-plus" id="ref-for-mult-one-plus①">+</a>B [of <a class="production" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#identifier-value" id="ref-for-identifier-value⑥">&lt;custom-ident></a>]<a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#mult-opt" id="ref-for-mult-opt②">?</a>)
</pre>
   <p class="note" role="note"> <a class="css" data-link-type="maybe" href="#funcdef-nth" id="ref-for-funcdef-nth②">nth()</a> is not related to the page counter, which may reset and use various numbering schemes.</p>
   <p>When the <a class="css" data-link-type="maybe" href="#funcdef-nth" id="ref-for-funcdef-nth③">nth()</a> selector is applied to a named page, and that named page is part of a page-group (see below), it selects the nth page in the page group.</p>
   <div class="example" id="example-b3ec403f">
    <a class="self-link" href="#example-b3ec403f"></a> 
<pre>@page :nth(1)
</pre>
    <p>This selects the first page of the document.</p>
<pre>@page :nth(2n)
</pre>
     This selects all even document pages.
   </div>
   <h3 class="heading settled" data-level="3.2" id="document-sequence-selectors"><span class="secno">3.2. </span><span class="content"> Page groups </span><a class="self-link" href="#document-sequence-selectors"></a></h3>
    Many paginated documents have a repeating structure, consisting of many chapters, sections, or articles. The first page of each subdivision often requires special treatment, but <span>[CSS3PAGE]</span> doesn’t define a way to select the first page of each chapter (as distinct from the first page of the entire document). 
   <p>When the <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-page-3/#propdef-page" id="ref-for-propdef-page">page</a> property is applied to an element that also has a forced break property applied, a <span class="css">page group</span> is created. The <dfn data-dfn-type="dfn" data-noexport id="page-group">page group<a class="self-link" href="#page-group"></a></dfn> is the collection of all pages created by an instance of that element. When a new instance of the element is rendered, a new <span class="css">page group</span> is started.</p>
   <p>A page may be part of several page groups, as a given <span class="css">page group</span> may have ancestors or descendants that are part of another <span class="css">page group</span>.</p>
   <div class="example" id="example-79556a6d">
    <a class="self-link" href="#example-79556a6d"></a> CSS: 
<pre>div { page: A }
child { page: B }
</pre>
    <figure>
      <img alt src="images/PageGroups.001.jpg" width="480"> 
     <figcaption>A page may be part of several page groups.</figcaption>
    </figure>
     Note that page 5 can be selected in three ways: 
<pre>@page :nth(5 of A) /* will select 5th page of every &lt;div> */
@page :nth(1 of B) /* will select first page of every &lt;child> */
@page :nth(5)   /* will select 5th page of document */
</pre>
   </div>
   <div class="example" id="example-70adc1c6">
    <a class="self-link" href="#example-70adc1c6"></a> 
    <p>Consider the following HTML:</p>
<pre>&lt;div class="chapter">
&lt;h1>Chapter One&lt;/h1>
&lt;p>some text&lt;/p>
&lt;table class="broadside">
...
&lt;/table>
...
&lt;/div>
&lt;div class="chapter">
&lt;h1>Chapter Two&lt;/h1>
&lt;p>some text&lt;/p>
...
&lt;table class="broadside">
...
&lt;/table>
...
&lt;/div>

</pre>
    <p>And CSS:</p>
<pre>div.Chapter {
page: body;
}

div.broadside {
page: broadside;
}

</pre>
    <p>In this case, each chapter will form a separate page group. @page:nth(3 of body) will select the third page of each chapter, even if that page happens to use the “broadside” named page. @page:nth(1) will select only the first page of the document, as will @page:first.</p>
   </div>
   <h2 class="heading settled" data-level="4" id="leaders"><span class="secno">4. </span><span class="content"> Leaders (moved) </span><a class="self-link" href="#leaders"></a></h2>
   <p class="issue" id="issue-1a552eac"><a class="self-link" href="#issue-1a552eac"></a> Now described in <a data-link-type="biblio" href="#biblio-css3-content">[CSS3-CONTENT]</a></p>
   <h2 class="heading settled" data-level="5" id="cross-references"><span class="secno">5. </span><span class="content"> Cross-references (moved) </span><a class="self-link" href="#cross-references"></a></h2>
   <p class="issue" id="issue-1a552eac①"><a class="self-link" href="#issue-1a552eac①"></a> Now described in <a data-link-type="biblio" href="#biblio-css3-content">[CSS3-CONTENT]</a></p>
   <h2 class="heading settled" data-level="6" id="bookmarks"><span class="secno">6. </span><span class="content"> Bookmarks (moved) </span><a class="self-link" href="#bookmarks"></a></h2>
   <p class="issue" id="issue-1a552eac②"><a class="self-link" href="#issue-1a552eac②"></a> Now described in <a data-link-type="biblio" href="#biblio-css3-content">[CSS3-CONTENT]</a></p>
   <h2 class="no-num heading settled" id="former-wd-sections"><span class="content">Appendix A: Where Are They Now?</span><a class="self-link" href="#former-wd-sections"></a></h2>
   <p>Many sections which were in the <a href="https://www.w3.org/TR/2011/WD-css3-gcpm-20111129/">29 November 2011 Working Draft</a> have been moved to other specifications. Here are some notes on where things have moved.</p>
   <h3 class="heading settled" id="page-marks-and-bleed-area"><span class="content">Page marks and bleed area</span><a class="self-link" href="#page-marks-and-bleed-area"></a></h3>
   <p class="note" role="note">This section has been moved to <a href="https://drafts.csswg.org/css-page/#marks">CSS Paged Media Module Level 3</a>.</p>
   <h3 class="heading settled" id="cmyk-colors"><span class="content">CMYK colors</span><a class="self-link" href="#cmyk-colors"></a></h3>
   <p class="note" role="note">This section has been moved to <a href="https://drafts.csswg.org/css-color/#cmyk-colors">CSS Color Module Level 4</a>.</p>
   <h3 class="heading settled" id="styling-blank-pages"><span class="content">Styling blank pages</span><a class="self-link" href="#styling-blank-pages"></a></h3>
   <p class="note" role="note">This section has been moved to <a href="https://drafts.csswg.org/css-page/#blank-pseudo">CSS Paged Media Module Level 3</a></p>
   <h3 class="heading settled" id="paged-presentations"><span class="content">Paged presentations</span><a class="self-link" href="#paged-presentations"></a></h3>
   <p class="note" role="note">This section has been moved to <a href="https://drafts.csswg.org/css-overflow-3/#paginated-overflow">CSS Overflow Module Level 3</a>.</p>
   <h3 class="heading settled" id="navigation-between-pages"><span class="content">Navigation between pages</span><a class="self-link" href="#navigation-between-pages"></a></h3>
   <p class="note" role="note">This is discussed in <a href="http://books.spec.whatwg.org/#spatial-layout-of-pages;-@layout">WHATWG CSS Books</a>.</p>
   <h3 class="heading settled" id="page-floats"><span class="content">Page floats</span><a class="self-link" href="#page-floats"></a></h3>
   <p class="note" role="note">This section has been moved to <a href="https://drafts.csswg.org/css-page-floats/">CSS Page Floats</a>.</p>
   <h3 class="heading settled" id="selecting-columns-and-pages"><span class="content">Selecting columns and pages</span><a class="self-link" href="#selecting-columns-and-pages"></a></h3>
   <p class="note" role="note">A brief mention of selecting columns is found in <a href="http://books.spec.whatwg.org/#selecting-columns">WHATWG CSS Books</a>.</p>
   <h2 class="no-num heading settled" id="ua-stylesheet"><span class="content">Appendix B: Default UA Stylesheet</span><a class="self-link" href="#ua-stylesheet"></a></h2>
   <p>This appendix is informative, and is to help UA developers to implement a default stylesheet for HTML, but UA developers are free to ignore or modify as appropriate. </p>
   <div class="example" id="example-0a0ebdaf">
    <a class="self-link" href="#example-0a0ebdaf"></a> 
<pre>@page {
  counter-reset: footnote;
  @footnote {
    counter-increment: footnote;
    float: bottom;
    column-span: all;
    height: auto;
  }
}

::footnote-marker {
  content: counter(footnote);
  list-style-position: inside;
}

::footnote-marker::after {
  content: '. ';
}

::footnote-call {
  content: counter(footnote);
  vertical-align: super;
  font-size: 65%;
}

@supports ( font-variant-position: super ) {
  ::footnote-call {
    content: counter(footnote);
    vertical-align: baseline;
    font-size: 100%;
    line-height: inherit;
    font-variant-position: super;
  }
}

h1 { bookmark-level: 1 }
h2 { bookmark-level: 2 }
h3 { bookmark-level: 3 }
h4 { bookmark-level: 4 }
h5 { bookmark-level: 5 }
h6 { bookmark-level: 6 }
</pre>
   </div>
   <h2 class="no-num heading settled" id="changes"><span class="content">Appendix C: Changes</span><a class="self-link" href="#changes"></a></h2>
   <p>Changes since the <a href="http://www.w3.org/TR/2014/WD-css-gcpm-3-20140513/">13 May 2014 Working Draft</a>:</p>
   <ul>
    <li>Clarify that bookmark is only created via <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-content-3/#propdef-bookmark-level" id="ref-for-propdef-bookmark-level">bookmark-level</a> property. Remove <span class="css">none</span> value from <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-content-3/#propdef-bookmark-label" id="ref-for-propdef-bookmark-label">bookmark-label</a>.
    <li>Move the cross references, leaders, and bookmarks sections to the <a href="https://www.w3.org/TR/css-content-3/">CSS Generated Content Module</a>.
   </ul>
   <p>Changes since the <a href="https://hg.csswg.org/drafts/raw-file/6a5c44d11c2b/css-gcpm/Overview.html">24 September 2013 Editor’s Draft</a>:</p>
   <ul>
    <li>The spec has a new editor.
    <li>All text and examples rewritten.
    <li>Added <span class="css">attr(&lt;identifier>)</span> value to <a class="property" data-link-type="propdesc" href="#propdef-string-set" id="ref-for-propdef-string-set②">string-set</a> property. This is supported by both Prince and AntennaHouse.
    <li>Added <a class="property" data-link-type="propdesc" href="#propdef-footnote-policy" id="ref-for-propdef-footnote-policy①">footnote-policy</a> property to control rendering of footnotes in difficult situations.
    <li>Added <a class="property" data-link-type="propdesc" href="#propdef-footnote-display" id="ref-for-propdef-footnote-display①">footnote-display</a> property to allow inline footnotes.
    <li>Removed sidenotes section.
    <li>Removed section on selecting elements within pages and columns
    <li>Removed page-group property, and added optional argument to nth() page pseudo-class to allow selection within page groups.
   </ul>
   <p>Changes since the <a href="https://www.w3.org/TR/2011/WD-css3-gcpm-20111129/">29 November 2011 Working Draft</a>:</p>
   <ul>
    <li> Page Marks and Bleeds section moved to <a href="https://drafts.csswg.org/css-page/#marks">CSS Paged Media Module Level 3</a> 
    <li> CMYK Colors section moved to <a href="https://drafts.csswg.org/css-color/#cmyk-colors">CSS Colors Level 4</a>. 
    <li> Styling Blank Pages section deleted 
    <li> Paged Presentations section moved to <a href="https://drafts.csswg.org/css-overflow-3/#paginated-overflow">CSS Overflow Module Level 3</a>. 
    <li> Navigation Between Pages moved to <a href="http://books.spec.whatwg.org/#spatial-layout-of-pages;-@layout">WHATWG CSS Books</a> 
    <li> Page floats section moved to <a href="https://drafts.csswg.org/css-page-floats/">CSS Page Floats</a> 
    <li> First-page pseudo-element section deleted 
    <li> Selecting Columns and Pages section deleted 
    <li> env() function removed from string-set property 
    <li> alignment values of leaders removed 
    <li> leader specified to occupy only a single line 
    <li> content() value of target-text changed to content(text) 
    <li> target-pull() value of content property removed 
   </ul>
   <p>Differences with the <a href="http://books.spec.whatwg.org/">WHATWG CSS Books</a> specification:</p>
   <ul>
    <li>Added <span class="css">attr(&lt;identifier>)</span> value to <a class="property" data-link-type="propdesc" href="#propdef-string-set" id="ref-for-propdef-string-set③">string-set</a> property. This is supported by both Prince and AntennaHouse.
    <li> <a href="http://books.spec.whatwg.org/">CSS Books</a> does not have the <a href="#propdef-footnote-display" id="ref-for-propdef-footnote-display②">footnote-display</a> property.
    <li> <a href="http://books.spec.whatwg.org/">CSS Books</a> does not have the <a href="#footnote-policy">footnote-policy</a> property.
    <li> The relationship between the <code>nth()</code> page pseudo-class and the page-group concept is clarified, which may make the page-group property redundant. 
    <li> This specification does not redefine the <code>:first</code> page pseudo-selector to select the first page of a page-group. 
    <li>
      This specification does not consider: 
     <ol>
      <li> Named areas 
      <li> Selecting elements within pages 
      <li> The <code>range()</code> page pseudo-class 
      <li> Selecting columns 
      <li> Baseline rhythms 
      <li> Extending the box model 
      <li> Character substitution 
      <li> Microtypography 
     </ol>
   </ul>
   <h2 class="no-num heading settled" id="acknowledgments"><span class="content"> Acknowledgments </span><a class="self-link" href="#acknowledgments"></a></h2>
    This work would not be possible without the immense contributions of Håkon Wium Lie. 
   <p>Chris Lilley, Elika J. Etemad, Alan Stearns, L. David Baron, Bert Bos, Florian Rivoal, [$your_name, ", " ]+ and Liam Quin have provided valuable feedback.</p>
  </main>
  <h2 class="no-ref no-num heading settled" id="conformance"><span class="content"> Conformance</span><a class="self-link" href="#conformance"></a></h2>
  <h3 class="heading settled" id="document-conventions"><span class="content"> Document conventions</span><a class="self-link" href="#document-conventions"></a></h3>
  <p>Conformance requirements are expressed with a combination of
	descriptive assertions and RFC 2119 terminology. The key words “MUST”,
	“MUST NOT”, “REQUIRED”, “SHALL”, “SHALL NOT”, “SHOULD”, “SHOULD NOT”,
	“RECOMMENDED”, “MAY”, and “OPTIONAL” in the normative parts of this
	document are to be interpreted as described in RFC 2119.
	However, for readability, these words do not appear in all uppercase
	letters in this specification. </p>
  <p>All of the text of this specification is normative except sections
	explicitly marked as non-normative, examples, and notes. <a data-link-type="biblio" href="#biblio-rfc2119">[RFC2119]</a> </p>
  <p>Examples in this specification are introduced with the words “for example”
	or are set apart from the normative text with <code>class="example"</code>,
	like this: </p>
  <div class="example" id="example-ae2b6bc0">
   <a class="self-link" href="#example-ae2b6bc0"></a> 
   <p>This is an example of an informative example. </p>
  </div>
  <p>Informative notes begin with the word “Note” and are set apart from the
	normative text with <code>class="note"</code>, like this: </p>
  <p class="note" role="note">Note, this is an informative note. </p>
  <p>Advisements are normative sections styled to evoke special attention and are
	set apart from other normative text with <code>&lt;strong class="advisement"></code>, like
	this: <strong class="advisement"> UAs MUST provide an accessible alternative. </strong> </p>
  <h3 class="heading settled" id="conform-classes"><span class="content"> Conformance classes</span><a class="self-link" href="#conform-classes"></a></h3>
  <p>Conformance to this specification
	is defined for three conformance classes: </p>
  <dl>
   <dt>style sheet 
   <dd>A <a href="http://www.w3.org/TR/CSS2/conform.html#style-sheet">CSS
			style sheet</a>. 
   <dt>renderer 
   <dd>A <a href="http://www.w3.org/TR/CSS2/conform.html#user-agent">UA</a> that interprets the semantics of a style sheet and renders
			documents that use them. 
   <dt>authoring tool 
   <dd>A <a href="http://www.w3.org/TR/CSS2/conform.html#user-agent">UA</a> that writes a style sheet. 
  </dl>
  <p>A style sheet is conformant to this specification
	if all of its statements that use syntax defined in this module are valid
	according to the generic CSS grammar and the individual grammars of each
	feature defined in this module. </p>
  <p>A renderer is conformant to this specification
	if, in addition to interpreting the style sheet as defined by the
	appropriate specifications, it supports all the features defined
	by this specification by parsing them correctly
	and rendering the document accordingly. However, the inability of a
	UA to correctly render a document due to limitations of the device
	does not make the UA non-conformant. (For example, a UA is not
	required to render color on a monochrome monitor.) </p>
  <p>An authoring tool is conformant to this specification
	if it writes style sheets that are syntactically correct according to the
	generic CSS grammar and the individual grammars of each feature in
	this module, and meet all other conformance requirements of style sheets
	as described in this module. </p>
  <h3 class="heading settled" id="conform-responsible"><span class="content"> Requirements for Responsible Implementation of CSS</span><a class="self-link" href="#conform-responsible"></a></h3>
  <p>The following sections define several conformance requirements
		for implementing CSS responsibly,
		in a way that promotes interoperability in the present and future. </p>
  <h4 class="heading settled" id="conform-partial"><span class="content"> Partial Implementations</span><a class="self-link" href="#conform-partial"></a></h4>
  <p>So that authors can exploit the forward-compatible parsing rules to assign fallback values, <strong>CSS renderers <em>must</em> treat as invalid
		(and <a href="http://www.w3.org/TR/CSS2/conform.html#ignore">ignore as appropriate</a>)
		any at-rules, properties, property values, keywords, and other syntactic constructs
		for which they have no usable level of support</strong>.
		In particular, user agents <em>must not</em> selectively ignore
		unsupported property values and honor supported values in a single multi-value property declaration:
		if any value is considered invalid (as unsupported values must be),
		CSS requires that the entire declaration be ignored. </p>
  <h4 class="heading settled" id="conform-future-proofing"><span class="content"> Implementations of Unstable and Proprietary Features</span><a class="self-link" href="#conform-future-proofing"></a></h4>
  <p>To avoid clashes with future stable CSS features,
		the CSSWG recommends <a href="http://www.w3.org/TR/CSS/#future-proofing">following best practices</a> for the implementation of <a href="http://www.w3.org/TR/CSS/#unstable">unstable</a> features and <a href="http://www.w3.org/TR/CSS/#proprietary-extension">proprietary extensions</a> to CSS. </p>
  <h4 class="heading settled" id="conform-testing"><span class="content"> Implementations of CR-level Features</span><a class="self-link" href="#conform-testing"></a></h4>
  <p>Once a specification reaches the Candidate Recommendation stage,
		implementers should release an <a data-link-type="dfn" href="http://www.w3.org/TR/CSS/#vendor-prefix">unprefixed</a> implementation
		of any CR-level feature they can demonstrate
		to be correctly implemented according to spec,
		and should avoid exposing a prefixed variant of that feature. </p>
  <p>To establish and maintain the interoperability of CSS across
		implementations, the CSS Working Group requests that non-experimental
		CSS renderers submit an implementation report (and, if necessary, the
		testcases used for that implementation report) to the W3C before
		releasing an unprefixed implementation of any CSS features. Testcases
		submitted to W3C are subject to review and correction by the CSS
		Working Group. </p>
  <p>
   Further information on submitting testcases and implementation reports
		can be found from on the CSS Working Group’s website at <a href="http://www.w3.org/Style/CSS/Test/">http://www.w3.org/Style/CSS/Test/</a>.
		Questions should be directed to the <a href="http://lists.w3.org/Archives/Public/public-css-testsuite">public-css-testsuite@w3.org</a> mailing list. 
<script src="https://www.w3.org/scripts/TR/2016/fixup.js"></script>
  </p>
  <h2 class="no-num no-ref heading settled" id="index"><span class="content">Index</span><a class="self-link" href="#index"></a></h2>
  <h3 class="no-num no-ref heading settled" id="index-defined-here"><span class="content">Terms defined by this specification</span><a class="self-link" href="#index-defined-here"></a></h3>
  <ul class="index">
   <li><a href="#valdef-footnote-policy-auto">auto</a><span>, in §2.8</span>
   <li>
    block
    <ul>
     <li><a href="#valdef-footnote-policy-block">value for footnote-policy</a><span>, in §2.8</span>
     <li><a href="#footnote-display-block">value for propdef-footnote-display</a><span>, in §2.3</span>
    </ul>
   <li><a href="#footnote-display-compact">compact</a><span>, in §2.3</span>
   <li><a href="#funcdef-content">content()</a><span>, in §1.1.1.1</span>
   <li><a href="#content-list">content-list</a><span>, in §1.1.1</span>
   <li><a href="#funcdef-element">element()</a><span>, in §1.2.2</span>
   <li><a href="#entry-value">entry value</a><span>, in §1.1.1.1</span>
   <li><a href="#exit-value">exit value</a><span>, in §1.1.1.1</span>
   <li><a href="#valdef-float-footnote">footnote</a><span>, in §2.3</span>
   <li><a href="#footnote-counter">footnote counter</a><span>, in §2.5</span>
   <li><a href="#propdef-footnote-display">footnote-display</a><span>, in §2.3</span>
   <li><a href="#propdef-footnote-policy">footnote-policy</a><span>, in §2.8</span>
   <li><a href="#footnote-display-inline">inline</a><span>, in §2.3</span>
   <li><a href="#footnote-policy-line">line</a><span>, in §2.8</span>
   <li><a href="#named-string">named string</a><span>, in §1</span>
   <li><a href="#funcdef-nth">nth()</a><span>, in §3.1</span>
   <li><a href="#page-group">page group</a><span>, in §3.2</span>
   <li><a href="#page-selectors">page selectors</a><span>, in §3</span>
   <li><a href="#funcdef-running">running()</a><span>, in §1.2.1</span>
   <li><a href="#propdef-running">running</a><span>, in §1.2.1</span>
   <li><a href="#running-elements0">Running elements</a><span>, in §1</span>
   <li><a href="#funcdef-string">string()</a><span>, in §1.1.2</span>
   <li><a href="#propdef-string-set">string-set</a><span>, in §1.1.1</span>
  </ul>
  <aside class="dfn-panel" data-for="term-for-propdef-position">
   <a href="https://drafts.csswg.org/css-position-3/#propdef-position">https://drafts.csswg.org/css-position-3/#propdef-position</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-position">1.2.1. 
The running() value </a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-mult-zero-plus">
   <a href="https://drafts.csswg.org/css-values-4/#mult-zero-plus">https://drafts.csswg.org/css-values-4/#mult-zero-plus</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-mult-zero-plus">1.1.1. 
	The string-set property </a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-mult-one-plus">
   <a href="https://drafts.csswg.org/css-values-4/#mult-one-plus">https://drafts.csswg.org/css-values-4/#mult-one-plus</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-mult-one-plus">1.1.1. 
	The string-set property </a>
    <li><a href="#ref-for-mult-one-plus①">3.1. 
Page Selectors </a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-comb-comma">
   <a href="https://drafts.csswg.org/css-values-4/#comb-comma">https://drafts.csswg.org/css-values-4/#comb-comma</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-comb-comma">1.1.1. 
	The string-set property </a>
    <li><a href="#ref-for-comb-comma①">1.1.2. 
	The string() function </a>
    <li><a href="#ref-for-comb-comma②">1.2.2. 
The element() value </a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-identifier-value">
   <a href="https://drafts.csswg.org/css-values-4/#identifier-value">https://drafts.csswg.org/css-values-4/#identifier-value</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-identifier-value">1.1.1. 
	The string-set property </a> <a href="#ref-for-identifier-value①">(2)</a>
    <li><a href="#ref-for-identifier-value②">1.1.2. 
	The string() function </a>
    <li><a href="#ref-for-identifier-value③">1.2.1. 
The running() value </a> <a href="#ref-for-identifier-value④">(2)</a>
    <li><a href="#ref-for-identifier-value⑤">1.2.2. 
The element() value </a>
    <li><a href="#ref-for-identifier-value⑥">3.1. 
Page Selectors </a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-mult-opt">
   <a href="https://drafts.csswg.org/css-values-4/#mult-opt">https://drafts.csswg.org/css-values-4/#mult-opt</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-mult-opt">1.1.2. 
	The string() function </a>
    <li><a href="#ref-for-mult-opt①">1.2.2. 
The element() value </a>
    <li><a href="#ref-for-mult-opt②">3.1. 
Page Selectors </a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-comb-one">
   <a href="https://drafts.csswg.org/css-values-4/#comb-one">https://drafts.csswg.org/css-values-4/#comb-one</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-comb-one">1.1.1. 
	The string-set property </a> <a href="#ref-for-comb-one①">(2)</a> <a href="#ref-for-comb-one②">(3)</a> <a href="#ref-for-comb-one③">(4)</a> <a href="#ref-for-comb-one④">(5)</a>
    <li><a href="#ref-for-comb-one⑤">1.1.1.1. The content() function</a> <a href="#ref-for-comb-one⑥">(2)</a> <a href="#ref-for-comb-one⑦">(3)</a>
    <li><a href="#ref-for-comb-one⑧">1.1.2. 
	The string() function </a> <a href="#ref-for-comb-one⑨">(2)</a> <a href="#ref-for-comb-one①⓪">(3)</a>
    <li><a href="#ref-for-comb-one①①">1.2.2. 
The element() value </a> <a href="#ref-for-comb-one①②">(2)</a> <a href="#ref-for-comb-one①③">(3)</a>
    <li><a href="#ref-for-comb-one①④">2.3. 
	Types of footnotes </a> <a href="#ref-for-comb-one①⑤">(2)</a>
    <li><a href="#ref-for-comb-one①⑥">2.8. 
Rendering footnotes and footnote policy </a> <a href="#ref-for-comb-one①⑦">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-float">
   <a href="https://drafts.csswg.org/css2/visuren.html#propdef-float">https://drafts.csswg.org/css2/visuren.html#propdef-float</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-float">2.3. 
	Types of footnotes </a> <a href="#ref-for-propdef-float①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-max-height">
   <a href="https://drafts.csswg.org/css2/visudet.html#propdef-max-height">https://drafts.csswg.org/css2/visudet.html#propdef-max-height</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-max-height">2.4.2. Size of the footnote area</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-typedef-content-content-list">
   <a href="https://drafts.csswg.org/css-content-3/#typedef-content-content-list">https://drafts.csswg.org/css-content-3/#typedef-content-content-list</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-typedef-content-content-list">1.1.1. 
	The string-set property </a> <a href="#ref-for-typedef-content-content-list①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-bookmark-label">
   <a href="https://drafts.csswg.org/css-content-3/#propdef-bookmark-label">https://drafts.csswg.org/css-content-3/#propdef-bookmark-label</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-bookmark-label">Appendix C: Changes</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-bookmark-level">
   <a href="https://drafts.csswg.org/css-content-3/#propdef-bookmark-level">https://drafts.csswg.org/css-content-3/#propdef-bookmark-level</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-bookmark-level">Appendix C: Changes</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-content">
   <a href="https://drafts.csswg.org/css-content-3/#propdef-content">https://drafts.csswg.org/css-content-3/#propdef-content</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-content">1.1.2. 
	The string() function </a>
    <li><a href="#ref-for-propdef-content①">1.2.2. 
The element() value </a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-page">
   <a href="https://drafts.csswg.org/css-page-3/#propdef-page">https://drafts.csswg.org/css-page-3/#propdef-page</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-page">3.2. 
Page groups </a>
   </ul>
  </aside>
  <h3 class="no-num no-ref heading settled" id="index-defined-elsewhere"><span class="content">Terms defined by reference</span><a class="self-link" href="#index-defined-elsewhere"></a></h3>
  <ul class="index">
   <li>
    <a data-link-type="biblio">[css-position-3]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-propdef-position" style="color:initial">position</span>
    </ul>
   <li>
    <a data-link-type="biblio">[css-values-4]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-mult-zero-plus" style="color:initial">*</span>
     <li><span class="dfn-paneled" id="term-for-mult-one-plus" style="color:initial">+</span>
     <li><span class="dfn-paneled" id="term-for-comb-comma" style="color:initial">,</span>
     <li><span class="dfn-paneled" id="term-for-identifier-value" style="color:initial">&lt;custom-ident></span>
     <li><span class="dfn-paneled" id="term-for-mult-opt" style="color:initial">?</span>
     <li><span class="dfn-paneled" id="term-for-comb-one" style="color:initial">|</span>
    </ul>
   <li>
    <a data-link-type="biblio">[CSS21]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-propdef-float" style="color:initial">float</span>
     <li><span class="dfn-paneled" id="term-for-propdef-max-height" style="color:initial">max-height</span>
    </ul>
   <li>
    <a data-link-type="biblio">[CSS3-CONTENT]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-typedef-content-content-list" style="color:initial">&lt;content-list></span>
     <li><span class="dfn-paneled" id="term-for-propdef-bookmark-label" style="color:initial">bookmark-label</span>
     <li><span class="dfn-paneled" id="term-for-propdef-bookmark-level" style="color:initial">bookmark-level</span>
     <li><span class="dfn-paneled" id="term-for-propdef-content" style="color:initial">content</span>
    </ul>
   <li>
    <a data-link-type="biblio">[CSS3PAGE]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-propdef-page" style="color:initial">page</span>
    </ul>
  </ul>
  <h2 class="no-num no-ref heading settled" id="references"><span class="content">References</span><a class="self-link" href="#references"></a></h2>
  <h3 class="no-num no-ref heading settled" id="normative"><span class="content">Normative References</span><a class="self-link" href="#normative"></a></h3>
  <dl>
   <dt id="biblio-css-position-3">[CSS-POSITION-3]
   <dd>Rossen Atanassov; Arron Eicholz. <a href="https://www.w3.org/TR/css-position-3/">CSS Positioned Layout Module Level 3</a>. 17 May 2016. WD. URL: <a href="https://www.w3.org/TR/css-position-3/">https://www.w3.org/TR/css-position-3/</a>
   <dt id="biblio-css-values-4">[CSS-VALUES-4]
   <dd>Tab Atkins Jr.; Elika Etemad. <a href="https://www.w3.org/TR/css-values-4/">CSS Values and Units Module Level 4</a>. 31 January 2019. WD. URL: <a href="https://www.w3.org/TR/css-values-4/">https://www.w3.org/TR/css-values-4/</a>
   <dt id="biblio-css21">[CSS21]
   <dd>Bert Bos; et al. <a href="https://www.w3.org/TR/CSS2/">Cascading Style Sheets Level 2 Revision 1 (CSS 2.1) Specification</a>. 7 June 2011. REC. URL: <a href="https://www.w3.org/TR/CSS2/">https://www.w3.org/TR/CSS2/</a>
   <dt id="biblio-css3-content">[CSS3-CONTENT]
   <dd>Elika Etemad; Dave Cramer. <a href="https://www.w3.org/TR/css-content-3/">CSS Generated Content Module Level 3</a>. 2 June 2016. WD. URL: <a href="https://www.w3.org/TR/css-content-3/">https://www.w3.org/TR/css-content-3/</a>
   <dt id="biblio-css3page">[CSS3PAGE]
   <dd>Elika Etemad; Simon Sapin. <a href="https://www.w3.org/TR/css-page-3/">CSS Paged Media Module Level 3</a>. 18 October 2018. WD. URL: <a href="https://www.w3.org/TR/css-page-3/">https://www.w3.org/TR/css-page-3/</a>
   <dt id="biblio-rfc2119">[RFC2119]
   <dd>S. Bradner. <a href="https://tools.ietf.org/html/rfc2119">Key words for use in RFCs to Indicate Requirement Levels</a>. March 1997. Best Current Practice. URL: <a href="https://tools.ietf.org/html/rfc2119">https://tools.ietf.org/html/rfc2119</a>
  </dl>
  <h3 class="no-num no-ref heading settled" id="informative"><span class="content">Informative References</span><a class="self-link" href="#informative"></a></h3>
  <dl>
   <dt id="biblio-css3list">[CSS3LIST]
   <dd>Elika Etemad; Tab Atkins Jr.. <a href="https://www.w3.org/TR/css-lists-3/">CSS Lists Module Level 3</a>. 25 April 2019. WD. URL: <a href="https://www.w3.org/TR/css-lists-3/">https://www.w3.org/TR/css-lists-3/</a>
   <dt id="biblio-css3syn">[CSS3SYN]
   <dd>Tab Atkins Jr.; Simon Sapin. <a href="https://www.w3.org/TR/css-syntax-3/">CSS Syntax Module Level 3</a>. 20 February 2014. CR. URL: <a href="https://www.w3.org/TR/css-syntax-3/">https://www.w3.org/TR/css-syntax-3/</a>
   <dt id="biblio-css3val">[CSS3VAL]
   <dd>Tab Atkins Jr.; Elika Etemad. <a href="https://www.w3.org/TR/css-values-3/">CSS Values and Units Module Level 3</a>. 31 January 2019. CR. URL: <a href="https://www.w3.org/TR/css-values-3/">https://www.w3.org/TR/css-values-3/</a>
   <dt id="biblio-dpub-latinreq">[DPUB-LATINREQ]
   <dd>Dave Cramer. <a href="https://www.w3.org/TR/dpub-latinreq/">Requirements for Latin Text Layout and Pagination</a>. 30 September 2014. WD. URL: <a href="https://www.w3.org/TR/dpub-latinreq/">https://www.w3.org/TR/dpub-latinreq/</a>
  </dl>
  <h2 class="no-num no-ref heading settled" id="property-index"><span class="content">Property Index</span><a class="self-link" href="#property-index"></a></h2>
  <div class="big-element-wrapper">
   <table class="index">
    <thead>
     <tr>
      <th scope="col">Name
      <th scope="col">Value
      <th scope="col">Initial
      <th scope="col">Applies to
      <th scope="col">Inh.
      <th scope="col">%ages
      <th scope="col">Anim­ation type
      <th scope="col">Canonical order
      <th scope="col">Com­puted value
    <tbody>
     <tr>
      <th scope="row"><a class="css" data-link-type="property" href="#propdef-footnote-display" id="ref-for-propdef-footnote-display③">footnote-display</a>
      <td>block | inline | compact
      <td>block
      <td>elements
      <td>no
      <td>N/A
      <td>discrete
      <td>per grammar
      <td>specified value
     <tr>
      <th scope="row"><a class="css" data-link-type="property" href="#propdef-footnote-policy" id="ref-for-propdef-footnote-policy②">footnote-policy</a>
      <td>auto | line | block
      <td>auto
      <td>elements
      <td>no
      <td>N/A
      <td>discrete
      <td>per grammar
      <td>specified value
     <tr>
      <th scope="row"><a class="css" data-link-type="property" href="#propdef-running" id="ref-for-propdef-running">running</a>
      <td>&lt;custom-ident>
      <td>none
      <td>elements
      <td>no
      <td>N/A
      <td>discrete
      <td>per grammar
      <td>specified value
     <tr>
      <th scope="row"><a class="css" data-link-type="property" href="#propdef-string-set" id="ref-for-propdef-string-set④">string-set</a>
      <td>[[ &lt;custom-ident> &lt;content-list>] [, &lt;custom-ident> &lt;content-list>]* ] | none
      <td>none
      <td>all elements, but not pseudo-elements
      <td>no
      <td>N/A
      <td>discrete
      <td>per grammar
      <td>specified value
   </table>
  </div>
  <h2 class="no-num no-ref heading settled" id="issues-index"><span class="content">Issues Index</span><a class="self-link" href="#issues-index"></a></h2>
  <div style="counter-reset:issue">
   <div class="issue">How do we define the default value for this function?<a href="#issue-edcf4ca2"> ↵ </a></div>
   <div class="issue">
    <p>This idea would be much more useful if we could also copy (rather than just move) elements. That would avoid the duplication of HTML in the example above. </p>
    <p>Bert Bos has proposed an alternative syntax, which allows both moving and copying elements into running heads. In the example below, h2 elements appear in their normal place in the document, but are also copied into running heads.</p>
    <div class="example">
<pre>h2 {
display: block;
running: chapter;
font-size: 18pt;
font-weight: bold;
}

h2:running {
display: inline;
font-size: 11pt;
font-weight: normal;
font-variant: small-caps;
letter-spacing: 1pt;
}

@page {
  @top-center {
    content: element(chapter);
    }
  }
</pre>
    </div>
    <table class="def propdef" data-link-for-hint="<dfn id=&quot;running-property&quot;>running</dfn>">
     <tbody>
      <tr>
       <th>Name:
       <td><span>running</span>
      <tr class="value">
       <th><a href="https://drafts.csswg.org/css-values/#value-defs">Value:</a>
       <td class="prod"><a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#identifier-value">&lt;custom-ident></a>
      <tr>
       <th><a href="https://drafts.csswg.org/css-cascade/#initial-values">Initial:</a>
       <td>none
      <tr>
       <th>Applies to:
       <td>elements
      <tr>
       <th><a href="https://drafts.csswg.org/css-cascade/#inherited-property">Inherited:</a>
       <td>no
      <tr>
       <th><a href="https://drafts.csswg.org/css-values/#percentages">Percentages:</a>
       <td>N/A
      <tr>
       <th><a href="https://drafts.csswg.org/css-cascade/#computed">Computed value:</a>
       <td>specified value
      <tr>
       <th>Canonical order:
       <td>per grammar
      <tr>
       <th><a href="https://drafts.csswg.org/web-animations/#animation-type">Animation type:</a>
       <td>discrete
    </table>
    <p class="all-media">User Agents are expected to support this property on all media, including non-visual ones.</p>
     <a href="#issue-929df450"> ↵ </a>
   </div>
   <div class="issue">Why is float:bottom used with the footnote area? Floating footnotes to the footnote area, and then floating the footnote area itself, seems overly complex, given that implementations don’t allow the footnote area to float anywhere else. Note that some implementations do allow the footnote area to be absolutely positioned.<a href="#issue-4af1f674"> ↵ </a></div>
   <div class="issue">How would one describe this in the grammar of CSS3-Page?<a href="#issue-829ce977"> ↵ </a></div>
   <div class="issue">How do footnotes work in multi-column text? Prince uses <code>float: prince-column-footnote</code> to create a footnote at the bottom of a column rather than the bottom of a page.<a href="#issue-069a39a3"> ↵ </a></div>
   <div class="issue">Implementations that support footnotes generally support page floats like <code>float: bottom</code>. Page floats should end up above the footnote area. How might this be specified?<a href="#issue-34f910d8"> ↵ </a></div>
   <div class="issue">We need an algorithm for laying out footnotes<a href="#issue-da883bb8"> ↵ </a></div>
   <div class="issue"> Now described in <a data-link-type="biblio" href="#biblio-css3-content">[CSS3-CONTENT]</a><a href="#issue-1a552eac"> ↵ </a></div>
   <div class="issue"> Now described in <a data-link-type="biblio" href="#biblio-css3-content">[CSS3-CONTENT]</a><a href="#issue-1a552eac①"> ↵ </a></div>
   <div class="issue"> Now described in <a data-link-type="biblio" href="#biblio-css3-content">[CSS3-CONTENT]</a><a href="#issue-1a552eac②"> ↵ </a></div>
  </div>
  <aside class="dfn-panel" data-for="propdef-string-set">
   <b><a href="#propdef-string-set">#propdef-string-set</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-string-set">1.1. 
	Named strings </a>
    <li><a href="#ref-for-propdef-string-set①">1.1.1. 
	The string-set property </a>
    <li><a href="#ref-for-propdef-string-set②">Appendix C: Changes</a> <a href="#ref-for-propdef-string-set③">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="funcdef-content">
   <b><a href="#funcdef-content">#funcdef-content</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-funcdef-content">1.1.1. 
	The string-set property </a>
    <li><a href="#ref-for-funcdef-content①">1.1.1.1. The content() function</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="funcdef-string">
   <b><a href="#funcdef-string">#funcdef-string</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-funcdef-string">1.1. 
	Named strings </a> <a href="#ref-for-funcdef-string①">(2)</a>
    <li><a href="#ref-for-funcdef-string②">1.1.1.1. The content() function</a>
    <li><a href="#ref-for-funcdef-string③">1.1.2. 
	The string() function </a> <a href="#ref-for-funcdef-string④">(2)</a> <a href="#ref-for-funcdef-string⑤">(3)</a>
    <li><a href="#ref-for-funcdef-string⑥">1.2.2. 
The element() value </a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="funcdef-running">
   <b><a href="#funcdef-running">#funcdef-running</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-funcdef-running">1.2. 
	Running elements </a>
    <li><a href="#ref-for-funcdef-running①">1.2.1. 
The running() value </a>
    <li><a href="#ref-for-funcdef-running②">1.2.2. 
The element() value </a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="funcdef-element">
   <b><a href="#funcdef-element">#funcdef-element</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-funcdef-element">1.2. 
	Running elements </a>
    <li><a href="#ref-for-funcdef-element①">1.2.1. 
The running() value </a>
    <li><a href="#ref-for-funcdef-element②">1.2.2. 
The element() value </a> <a href="#ref-for-funcdef-element③">(2)</a> <a href="#ref-for-funcdef-element④">(3)</a> <a href="#ref-for-funcdef-element⑤">(4)</a> <a href="#ref-for-funcdef-element⑥">(5)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="propdef-footnote-display">
   <b><a href="#propdef-footnote-display">#propdef-footnote-display</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-footnote-display">2.3. 
	Types of footnotes </a>
    <li><a href="#ref-for-propdef-footnote-display①">Appendix C: Changes</a> <a href="#ref-for-propdef-footnote-display">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="propdef-footnote-policy">
   <b><a href="#propdef-footnote-policy">#propdef-footnote-policy</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-footnote-policy">2.8. 
Rendering footnotes and footnote policy </a>
    <li><a href="#ref-for-propdef-footnote-policy①">Appendix C: Changes</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="footnote-policy-line">
   <b><a href="#footnote-policy-line">#footnote-policy-line</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-footnote-policy-line">2.8. 
Rendering footnotes and footnote policy </a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="funcdef-nth">
   <b><a href="#funcdef-nth">#funcdef-nth</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-funcdef-nth">3.1. 
Page Selectors </a> <a href="#ref-for-funcdef-nth①">(2)</a> <a href="#ref-for-funcdef-nth②">(3)</a> <a href="#ref-for-funcdef-nth③">(4)</a>
   </ul>
  </aside>
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    var hitALink = false;
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            // Clicking on a link in a <dfn> shouldn't summon the panel
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        // open the panel
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        // Switch it to "activated" state, which pins it.
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});
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